Assembly Of Functional Materials With Superamolecular Structure And Their Applications In Composite Materials

Layered double hydroxides (LDHs) are a calss of anionic lamellar functional materials. They have been attracted considerable attention due to their unique crustal structure and physical and chemical properties. The kind and amount of the metals constituting the host layers of LDHs and interlayer anions, which can be exchanged out, can be changed in a wide range. LDHs have widespread applications as anion-exchangers, adsorbents, catalysts or catalyst precursors, as optical, electrical and magnetic functional materials, and additives in polymers in the fields of industry, agriculture and so on.In this dissertation, we synthesized three kinds of intercalated layered supermolecular materials by intercalating functional anions into the interlayer of LDHs in order to improve the thermal stability of the functional anions and to get pigment, hight efficient IR adsorbent and UV adsobent with enhanced capacity. A detailed investigation has been carried out on the assembly, structures, compositions, performance of the supermolecular materials as well as their applications in macromolecule composite.The detailed contents and results are shown below:l.Acid Red114(denoted as NPDA) anion intercalated LDHs was prepared by ion-exchange method using ZnAl-NO3-LDHs which was prepared with separate nucleation and aging steps method as a precursor. The samples obtained were characterized by SEM, XRD, FT-IR, TG-DTA, ICP and UV-Vis. After intercalation of NPDA anions, the interlayer distance of the LDHs increases from0.87to2.18nm, confirming their incorporation into the interlayer galleries of the LDHs host. Infrared spectroscopy and thermogravimetric analysis revealed the presence of host-guest interactions between LDHs layers and NPDA anions. The thermal stability of NPDA and ZnAl-NPDA-LDHs were compared by thermogravimetric-differential thermal analysis, UV-visible spectroscopy and infrared spectroscopy. It was found that the thermal stability of NPDA anions was markedly improved by incorporation into the ZnAl-LDHs matrix, meanwhile the light fastness was also enhanced.2. N-Phosphonomethyl aminodiacetic acid (denoted as PMIDA) have been intercalated into a layered double hydroxide (LDHs) host by ion-exchange of an MgAl-NO3-LDHs precursor under a nitrogen atmosphere. The product has been characterized by SEM、XRD、FT-TR、 TG-DTA、UV-vis、ICP and TEM, indicating that PMIDA has been successfully intercalated into LDH. The intercalated material was mixed with low density polyethylene (LDPE) using a masterbatch method. LDPE film filled with the intercalated material showed a higher infrared absorption than films filled with MgAl-C03-LDH in the key9-11um range required for application in agricultural plastic films.3.2-Hydroxy-4-Methoxybenzophenone-5-Sulfonic acid (denoted as HMBA) has been intercalated into a layered double hydroxides (LDHs) host by ion-exchange reaction using MgAl-N03-LDHs as precursor. The samples obtained were characterized by SEM, XRD, FT-IR, TG-DTA and UV-Vis. The results show that the original interlayer nitrate anions of LDHs precursor can be completely replaced by HMBA anions. FT-IR and TG-DTA curves reveal the presence of a complex system of supramolecular host-guest interactions. MgAl-HMBA-LDHs, with fairly good thermal stability, can absorb UV radiation more effectively. The photostability of PP matrix modified by MgAl-HMBA-LDHs is enhanced comparing with the pristine PP matrix or PP matrix modified by HMBA.4. The synthesized supramolecular materials ZnAl-NPDA-LDHs and MgAl-HMBA-LDHs are seperately added into Fiberglass-Reinforced Plastics (denoted as FRP) matrix as colorant and UV adsorbent to afford color and UV inhibition protect for FRP matrix. It was found that the thermal stability and light fastness of ZnAl-NPDA-LDHs/FRP matrix are better than NPDA/FRP. The addition of ZnAl-NPDA-LDH and NPDA can improve the photo stability of FRP matrix. The test results indicate that MgAl-HMBA-LDHs/FRP matrix has better thermal stability and light fastness than HMBA/FRP matrix. The addition of MgAl-HMBA-LDHs can enhance both the thermal stability and light fastness of FRP matrix.